IN ENGLISHSince last year I have been thinking about the indigo-fructose vat. Last summer I made some experiments, but I then thought they had failed, and I didn't have time to repeat them. Now I think some of the experiments were successful, it seems this (too) is one of those things you have to try and try and learn through failure and success. Fructose vat works differently than reducing indigo with hydrosulfite, and I had been stuck to the thought how it should work and look (based on how hydrosulfite works), but this is different. When I had cleared my thoughts on that, it all seemed to make more sense.

I had posted last year where I began: Michel Garcia's fructose vat, and Anne Vuorema's study. In April this year there were very good discussion and experiences shared in Sustainable Natural Dye Practice- online discussion group. Thank you especially Jane, Robin, Ulrike and Helen. Also Jenny Dean had tried this fructose vat.There were couple of important things in fructose vat I hadn't understood earlier.Fructose/glucose does not reduce indigo by itself, it is most likely it's degradation products which reduce the indigo. The degradation of glucose depends on the concentration of the alkali and high temperature speeds up the degradation. So the pH needs to be 11 (or more) and temperature high (70-80°), at least in the beginning. Also unlike hydrosulfite vat, the concentration of indigo needs to be high. The more indigo there is compared to the volume of the liquid, the darker blue you get. This was also in Vuorema's study. Too much water makes this vat weak. If there is too much liquid the color becomes very pale blue, or if the pH is not high enough, indigo does not reduce properly. If the amount of liquid and indigo is ok, and the color still becomes pale, you can dip several times to darken the color.On the other hand this vat can be used for several days or even weeks, and you can dye the same color. At least when it is successful.

IN ENGLISHHere are experiments I did last week.Because in Anne Vuorema's study anthraquinones had been found to help in glucose reduction of indigo, and because last year also I got better results when I had added madder to the vat, I did so again.1. 5 litres water20g indigo mixed with almost boiling water0,5 dl used madder pieces40g slaked lime60g fructoseI added lime to the water, then indigo and madder, and raised the temperature to 60°C. I then added fructose and stirred carefully. After 10 minutes the vat had changed to yellow, and after 45 minutes there was a slight coppery sheen on the vat, no bubbles though. There was some sludge on the bottom, so I put some chicken wire in the bottom, so that the yarn would not come in contact with the sludge, and dye unevenly. I dyed in this vat 5 times 100g skeins, two 10 min dips for each and let the vat rest in between the skeins. Because there was only 5 litres of liquid, I could dye only one skin at a time, and so got five slightly different light blues, no 1 in the picture. The vat seemed the work well, but I had to stop because the night came:)

IN ENGLISHThe next day there was good coppery sheen on the vat, even though it's temperature was less than 20°C.pH had stayed high, 10-11.I dyed two skeins, again light blue like the day before. Then I let the vat to rest and did another experiment.--------------------------------------------------------------------------------------------------------------------------

IN ENGLISHLast year I had gotten good very dark blue when I had done it in closed glass jar, so I tried to do it now again.2. 1,8 litres water10g indigo mixed with almost boiling water20g slaked lime30g fructoseLike earlier I added lime to the water, then indigo and last the fructose. The water in double boiler was 70-80°C. Already after 5 minutes the vat was light yellow, picture above, and after 10 minutes the water was darker yellow. I didn't wait longer, but added 20 grams of yarn to the vat. Picture below. After 6 minutes I took it up and there was no color in the yarn. Not at all!! I couldn't understand it.

IN ENGLISHAfter I had taken the yarn from the vat, there were strange "clouds" in it. What are these?? Does anyone know what happened here?I let the vat be for an hour, and then most of the vat had cleared and the "clouds" sunk to the bottom. In the surface there was slight coppery sheen. I tried to dye again, and with two dips got very pale blue. I added some madder to the vat and after one hour dyed 20g of yarn with two dips, now the color became little darker blue than the first one. These are the two small skeins on to p of the big skeins, no 2, in the picture.-----------------------------------------------------------------------------------------------------------------------------

IN ENGLISH3. 6 litres water30g indigo mixed with almost boiling water60g slaked lime90g henna powderI added the lime to the water, then indigo and henna. I raised the temperature to 80°C, and let it cool down to 60°C in 90 minutes, after which time there was slight coppery sheen on the surface and also some hennabubbles.I dyed with this vat four 100g skeins, separately, and two 10 min dips with each. In between the dips I let the vat rest. The first skein became the darkest, and the next ones each a little lighter, This was unlike experiment no 1 where there were not very big differences in color of the skeins. In the picture these are no 3.This vat is still waiting for more dyeing, and it looks ok.----------------------------------------------------------------------------------------------------------------------------

IN ENGLISHAll these skeins have looked greenish or turqoise after dyeing, but when I have washed them after dyeing and oxydizing, the greenish shade has disappeared and they are nice clear blue. Where does this turqoise/greenish shade come from??

IN ENGLISHI combined the vats from experiment 1 and 2, raised the temperature to 65°C, and added 30g fructose. After half an hour I dyed two 100g skeins, separately, like earlier, and got light blue, like earlier. The vat was now quite dark yellow, and is still waiting for more dyeing.---------------------------------------------------------------------------------------------------------------------------

IN ENGLISHIn Sustainable Natural Dye Practice - discussions there were mentioned that besides fructose, also henna, ripe bananas, dates or almost any kind of fruit and even onions, can reduce indigo in this type of vat. This reminded me of a recipe to dye blue with indigo and turnips (lye, indigo and turnips) which was in Fredrika Runeberg's Recipebook. It is a booklet published by Porvoo Museum in 2003, the original was from somewhere in 19th century. Fredrika Runeberg lived 1804-1877 and she was a wife of a well know poet Johan Ludvig Runeberg, and also a writer herself. So this type of dyeing was already known then. i didn't have turnips, so I decided to try with onions.1.7 litres water10g indigo mixed with almost boiling water20g slaked lime180g onions from last year, without skins and cut to smaller piecesI added lime to the water, then indigo and then onions. I raised the temperature to 90°C, almost boiling, kept it there for two hours and slowly lowered to 65°C in another two hours.In the picture above there are lime and indigo in the jar.

THOUGHTSThese were only the first experments and there is a lot to learn about this method.Also I have to test if these are as light and rubfast as indigoyarns dyed with normal method.I would like to dye bigger amounts at a time, so the volume of the bath needs to be bigger. That means that I must also increase the amount of the indigo, but I'm going to try first with these smaller vats, so that it wouldn't cost so much even if the vat doesn't work. Even though now I feel this will work.Also I need to dye darker colors, and even though more dipping would darken the color, I'm hesitant to increase the dippings from two because it might damage the wool.This fructose vat is also called 1-2-3 vat, because according to Michel Garcia's recipe the ratio between indigo, slaked lime and fructose should be 1-2-3. And also the alkaline should be slaked lime (calcium hydroxide), which is alkaline enough. Washing soda is not alkaline enough. In Finland it is difficult to get calcium hydroxide on smaller amounts, or you can get it from stores which sell things for builders, but only on 25kg bags. It isn't expensive, but it is a lot to buy when you don't need so much, and it doesn't stay active for very long.I think it doesn't hurt to use more fructose, and it might be beneficial to add a little bit of madder (even used madder) to the vat.And the important thing is to remember the amount of water in relation to other ingredients. I think (but don't know for sure) that at the most 2 litres of water to 10g of indigo, 20g slaked lime and 20g (or more) of fructose is a good ratio, and if you use more water, you should also add more of the other ingredients. At least this is how I'm going to do now, but more about how it works later:)In the bottom of the dye vessel there is good to be something to separate the sludge from the yarns.And it is good wash the yarns after the dyeing before they dry (because of the alkalinity of the bath), and also soak them in vinegar water for couple of hours after washing, to remove the excess alkalinity, to keep the wool from getting damaged.

IN ENGLISHSummer goes by so fast. I have dyed all the time, but the yarns have gone to the market, where it is the the best season now. I'll add more yarns to the online-shop later, hopefully before end of the summer.This summer has been cooler than the previous two summers, more like normally it is here. The days have been mostly below 20C ( 68F) and nights closer to 10C (50F), and it has been raining more than usually. I have dyepots and barks fermenting in my greenhouse, but it takes longer to dye in cooler weather. Madder works fine even in this temperature, but I didn't try fermenting indigo this summer. It didn't work well even last summer when it was way hotter, so I don't think it will work when the night temperatures are this low. I have some solar dye glass jars, though, and they seem ok.

Japanese indigo also likes rains, but it hasn't liked cold nights. I had them covered with horticultural fleece all June, but I hadn't covered one bed and the japanese indigo there clearly suffered from cold. The edges of the leaves turned red. Now they are beginning to look normal and healthy.In the picture above there is a pointed leaf variety of japanese indigo.

The tree leaves are still good for harvesting. In the end of the summer the dyestuffs in them change and they don't yield so good colors as in the early summer. Long simmering may help with late summer leaves.------------------------------------------------------------------------------------------------------------------

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WHY USE NATURAL DYES

"We can keep the knowledge of their use alive, as well as regaining for ourselves a vital contact with the natural world. The ability to correctly identify the plants needed, to understand their growth stages sufficiently well to be able to obtain the greatest dye, offer both challenge and pleasure."

We sell our yarns, mitten kits, knitted things and my husband's photographs at the market Kauppatori in Helsinki. This week we will be at the market on Monday August 14th, Tuesday August 15th, Thursday August 17th and Saturday August 19th